Generally, a variety of high frequency devices are operable based on an electromagnetic interaction phenomenon described by the Maxwell's equation. Accordingly, a high frequency electromagnetic analysis is usually employed to analyze them. One of prior arts is well known as a design tool called Ansoft HFSS (High-Frequency Structure Simulator) developed by Ansoft Corp. in the United States.
This design tool developed by Ansoft Corp. is designed to involves automatically acquire the device characteristics of microwave, milliwave or wireless devices by solving the Maxwell's equation that is an operation principle for the high frequency devices, and can be used to determine the characteristics of antenna, transmission line, filter and connector by creating the shape of device to be analyzed using a three dimensional CAD interface, and setting up the material property values and an input/output port.
However, most of prior arts including the design tool developed by Ansoft Corp. make use of a Finite Element Method (FEM), and have the following problem:
In the Finite Element Method, the object having actually a complex shape and property is mesh divided into minimal units having a simple shape and property. Then, the characteristics of each element are approximately represented using a mathematical equation, and the simple equations are combined and solved simultaneously to predict the overall characteristics.
Therefore, the structure of an object to be analyzed must be mesh divided into simple minimal units required for the analysis, the units must be input into the three dimensional CAD, and the material property values for individual meshes must be specified. The procedure is time and labor intensive. Besides, the arithmetical operation spent several minutes to several hours in a super-computer class, and several days to several months in a workstation class, for example.
Accordingly, it is an object of the present invention to provide an apparatus and method for analyzing the distributed constant a transmission line to analyze the characteristics of the transmission line only by inputting the specific distributed parameters without mesh dividing the transmission line to be analyzed into minimal units required for the analysis, especially suitable for the transmission line included in a spiral layered type distributed constant filter.